Red Sox Manager Alex Cora, left, takes the ball from closer Kenley Jansen, second from right, during the ninth inning Friday in Boston. Jansen allowed three runs in the ninth and Boston lost to St. Louis, 8-6. Michael Dwyer/Associated Press

BOSTON — Nolan Gorman hit a go-ahead, two-run homer off Kenley Jansen in the ninth inning and the St. Louis Cardinals beat the Boston Red Sox 8-6 on Friday night to win their second straight series opener after losing their first 11 this season.

Nolan Arenado had a two-run homer during his four-hit night and Wilson Contreras added a solo shot for St. Louis, which blew a lead in the eighth inning but rebounded to win for the fourth time in five games.

James Paxton struck out nine over five innings in his first major league appearance in two years for the Red Sox. Enmanuel Valdez and Connor Wong homered on consecutive pitches off Cardinals starter Adam Wainwright.

Gorman belted his homer to right against Jansen (1-1), who became the seventh player to earn 400 saves on Wednesday night but couldn’t close this one. Gorman’s hit came after Lars Nootbaar’s single tied it.

“The biggest thing is to make sure you’re ready before they call your name,” Gorman said. “I go down there (in the indoor cage) to make sure my body’s ready, make sure my swing’s good and really just in between innings, look at the pitchers that might be coming in.”

Ryan Helsley (1-2) picked up the victory in relief, while Boston lost for just the third time in 12 games.

“It was a good win,” Arenado said. “They scored a lot of runs there, but we just kept fighting as an offense.”

Trailing 5-4 in the eighth, the Red Sox rallied against Génesis Cabrera. Rafael Devers’ ground-rule double tied it before pinch-hitter Raimel Tapia’s slow grounder scored pinch-runner Bobby Dalbec from third.

Wainwright gave up four runs and seven hits in five innings in just his second start of the season after missing the club’s first 33 games with a groin injury he suffered while working out during the World Baseball Classic.

The Cardinals overcame a 4-2 deficit with three runs in the sixth. Contreras opened the inning with his shot over Boston’s bullpen, Arenado scored the tying run on a double-play grounder and Nootbaar had an RBI single against reliever Richard Bleier.

Mixing mostly a fastball mostly at 96-97 mph with a cutter and curve, the 34-year-old Paxton gave up two runs in his first MLB game since April 6, 2021, when he was with Seattle. The lefty had Tommy John surgery in 2021 and started this season on the injured list with a strained right hamstring.

“It was awesome to get back out there to compete with these guys,” he said. “It was a long time. I was just focused on finding my rhythm out there and letting it rip. It felt pretty good coming out.”

Boston’s Jarren Duran had two-run single.

OOPS

A ball girl down the right-field line made a nice stab on Triston Casas’ hard shot after Duran’s tying single. The problem: It hit the chalk and was a fair ball. Casas was awarded a ground-rule double and the speedy Duran, who was on first, was put at third by the umpires. Kiké Hernández, the next batter, grounded out to end the inning.

GOOD FOLLOW UP

Wainwright was issued a pitch-clock violation that ended up being ball four to Duran. On the next pitch, he went over and covered first, making a nice stretch on an inning-ending 3-6-1 DP.